1. Field of the Invention (Technical Field)
This invention relates generally to the field of energetic materials management, and specifically destruction and disposal of decommissioned explosive devices and the energetic materials associated with such explosive devices.
2. Background Art
The United States Government, as well as other governmental entities and, in some instances, commercial concerns, face the challenge of disposing of undetonated explosive materials when the devices with which those materials are associated reach the end of their useful lives. Destruction of energetic materials is necessary, for example, in connection with demilitarization of bulk energetic materials and assembled munitions when those materials or munitions become obsolete or are determined to be excess or off-specification. It is estimated that current U.S. Department of Defense stockpile of energetic materials that needs to be destroyed is in the hundreds of thousands of tons, and it increases by approximately 60,000 tons per year. Other government agencies, including the U.S. Department of Energy, have significant amounts of weapons components that, likewise, need to be destroyed as part of stockpile maintenance.
Typically, such energetic materials are disposed of through what are called open burn/open detonation (OB/OD) operations. These operations involve, as the name suggests, detonating or simply burning energetic materials that have endured beyond their useful life, but that still retain explosive properties. A number of environmental and legal issues face those employing this method of disposal, however, including concerns associated with noise and shock pollution, metal spatter, and lead emissions.
A need remains for an economically and environmentally sound chemical process that will safely render explosives materials, such as RDX and TNT, non-explosive and yield a conveniently disposed waste product without generating significant amounts of toxic or environmentally harmful byproducts.
The present invention provides a method for chemically treating energetic materials and using the product of the treatment reaction as curing agent for polymer resin, thereby yielding a nonexplosive, stable product. This product may be conveniently disposed of according to procedures commonly used for disposal of polymeric materials as solid waste, or it could be used as a structural material for a number of applications such as adhesives. In the preferred embodiment of the present invention, energetic materials such as TNT (trinitrotoluene), RDX (cyclonite) and Composition B (a composition containing 40 percent TNT, 59 percent RDX, and 1 percent wax) are treated by reacting them with an organic amine at low temperatures. The reaction products then serve as curing agents for conventional epoxy resins to yield polymers that exhibit mechanical and thermal properties similar to conventional epoxy polymers. Commonly employed modes of analysis of energetic materials demonstrate that the explosives treated in the fashion described herein are no longer capable of being detonated.
Accordingly, it is an object of the present invention to provide an alternative to OB/OD operations for disposing of demilitarized energetic materials.
It is another object of the present invention to provide a method for depriving energetic materials of their explosive characteristics without creating significantly harmful environmental toxins in the process.
It is yet another object to provide a method for inactivating explosive materials which yields a stable waste product that may be conveniently disposed of using commonly used disposal modalities such as burial.
An advantage of the present invention is that various amine compounds, including commercially available amine-based epoxy curing agents, may be mixed with energetic materials and then combined with traditional epoxy resins to form the stable waste product.
Another advantage of the present invention is that it provides a method for rendering energetic materials non-explosive, the method comprising mixing the energetic material with a reagent comprising an amine to form a reaction product that is non-explosive.
Yet another advantage of the invention is that it provides a method for rendering energetic materials non-explosive, comprising mixing the energetic material with a reagent comprising an epoxy curing agent to form a reaction product that is non-explosive.
Yet another advantage of the invention is that it provides a new epoxy curing agent prepared by combining energetic material with a reagent selected from either conventional epoxy curing agents (for example commercial epoxy hardeners) and compounds comprising amines
These and other objects and advantages are satisfied by the method of the present invention wherein energetic materials are treated with amines to yield reaction products which, when combined with epoxy resin, cure the resin to form a stable, non-explosive epoxy resin product that can be conveniently disposed of using conventional disposal methods.
Other advantages and novel features will become apparent to those skilled in the art upon examination of the following description or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.